Calculus: Four good word problems in calculus

#1 A tumor may be regarded as a population of multiplying cells. It is found empirically that the "Birth Rate" of the cells in the tumor decrease exponentially with time, so that B(t)=B0e^(-at)... find the limiting population of the tumor.
(See attachment for full questions)

Attachments

Solution Summary

1. Population of cell multiplying exponentially with time is calculated.------------
2. The resistance of water varies with square of velocity, the distance covered by it before coming to rest is calculated.--------
3. Velocity and position for a body under drag as a function of time is calculated.---------
4. A body is projected up and under the varying gravity the position and velocity are calculated.----------

"Sorry I attached the wrong figure for this question but seems your answer is still right. May I resend the problem with the correct figure and let you to double check with it? If I may, how to attach the correct figure?"